Plain English Meaning

It means grading a student against their own potential, not against a fixed yardstick. The question is not 'did they meet a universal standard?' but 'are they performing as well as they personally can at this stage?'

Full Definition

In aviation instruction, a basis for assessing student performance in which evaluation is made against the student's individual capability rather than against an external or absolute standard. The instructor judges progress relative to what the student is capable of achieving, taking into account natural ability, prior experience, physical characteristics, and rate of learning.

Context Anchor

Seen in flight instruction when an instructor decides whether a learner is ready for the next step, such as solo flight, a new maneuver, or a practical test recommendation.

Derivation

From Latin demonstrare, 'to point out or show clearly,' combined with 'ability,' meaning to do something. Together: what the student has actually shown they can do — not what they might do, claim to do, or what others typically do.